In recent years, greening of building roofs, decks, and the like has been actively promoted. As a conventional technology regarding such greening of building roofs, Patent Document 1 (JP Patent Publication (Kokai) No. 2002-320408 A), as shown in FIG. 12(a), discloses a method for cultivation by installing a turf sheet 34 on the surface of a plant cultivation structure 31 provided with water retentivity using a porous material such as zeolite, so that plant roots can become settled in the gaps in the porous materials.
FIG. 12(b) shows a cross-sectional view of the plant cultivation structure 31 and a base 32 located thereunder of Patent Document 1 (JP Patent Publication (Kokai) No. 2002-320408 A). The base 32 is formed of a plastic or metal container capable of storing water, having a side surface 32a on the four sides. The base 32 is integrally fixed on the backside of the plant cultivation structure 31 by injecting zeolite as a porous material onto the upper portion of the base 32 and molding it at high pressure.
In an example shown in FIG. 12(c), a plurality of concave portions 33 are formed on the top surface (upper surface) of the plant cultivation structure 31 of Patent Document 1 (JP Patent Publication (Kokai) No. 2002-320408 A), such that plants can be cultivated by placing soil and seeds in individual concave portions 33.
Because the plant cultivation structure of the foregoing Patent Document 1 (JP Patent Publication (Kokai) No. 2002-320408 A) has plants take root in a porous material such as zeolite, only certain plants such as turf can be cultivated and flowering grasses, trees, or the like cannot be cultivated.
When a turf sheet is provided on the surface of the plant cultivation structure, there is no means for fixing the turf sheet. In order to prevent the turf sheet from being blown away by the wind or the like, a number of installed turf sheets may be entirely covered with a net or fixed with pins. However, such method involves very cumbersome construction.
When cultivating plants on a wall surface in pot planting, the soil in the pot may spill over when the pot is inclined sideways.
The invention has been made in consideration of such problems, and it is an object of the invention to provide a multipurpose planting base that can be easily installed on a concrete floor on a roof or the like, a slope, a folded-plate roof, or even on a wall surface or the like, and that enables turf planting, pot planting, and even pot planting on wall surfaces, without employing the conventional antiscattering net.